Maternal expulsion delivers the frank breech from the lower birth canal, while the contractile forces of the uterus maintain flexion of the fetal head.

Inappropriate traction on the breech at this point may lead to extension of the fetal head, or entrapment of an arm behind the head (nuchal arm).

After spontaneous expulsion of the breech to the umbilicus, the obstetrician delivers the extended legs. The fingers splint the thigh, while flexing and abducting the hip.

Note the lateral rotation of the thighs on the hips, to deliver the legs. The obstetrician must avoid the instinctive manoeuvre of hooking the thigh down, thus bending the knee in the wrong direction.

Note the lateral rotation of the thighs on the hips, to deliver the legs. The obstetrician must avoid the instinctive manoeuvre of hooking the thigh down, thus bending the knee in the wrong direction.

Further maternal efforts deliver the fetal abdomen and the obstetrician gently hooks down a loop of umbilical cord, to avoid occlusion of the circulation. At this point in the delivery, the breech should hang downwards, while maternal efforts expel the infant until the lower border of the scapula is visible below the pubic arch. Gentle traction by the obstetrician ensures the back does not rotate posteriorly. For delivery of the shoulders and arms, the obstetricians thumbs overlie the sacrum with the fingers around the iliac crests, so that the hands cradle the fetal pelvis.

If the fetal arms have not become extended, the obstetrician passes the index and middle fingers over the shoulder, and sweeps the left arm medially across the chest, thus delivering it.

If the fetal arms have extended, the obstetrician applies Lovset's manoeuvre. Lateral flexion of the fetus is exaggerated to enable descent of the posterior shoulder below the sacral promontory.

Lovset's manoeuvre. (Continued). The obstetrician then rotates the body with the back uppermost, 180 degrees. (b) The posterior shoulder has been rotated anteriorly, and lies beneath the symphysis. The obstetrician hooks the arm downwards, then rotates the body back 180 degrees, to deliver the other arm in the same manner.

Gentle elevation of the fetal trunk allows the obstetrician access to the fetal airway. The obstetrician must avoid over-extension, because of the risk of fetal cervical injury, with hyperextension of the fetal head.

Application of Piper's forceps to the fetal head, the preferred method of delivering the head.

When Piper's forceps have been applied, the fetal trunk, wrapped in a 'breech towel', is supported by one hand, while the other exerts gentle traction on the forceps in the direction of the pelvic axis (arrow).

While an assistant supports the fetal trunk, avoiding hyperextension, the obstetrician kneels, to facilitate application of the forceps, and subsequent traction in the axis of the pelvis.

The Mauriceau-Smellie-Veit manoeuvre, although not as desirable as Piper's forceps, can prove useful when events progress rapidly, and the obstetrician has inadequate time to apply forceps. The fetal trunk lies astride the obstetrician's forearm, and the obstetrician's middle finger, placed in the fetal mouth, gently flexes the head. The upper hand on the fetal back enables gentle downward and backward traction, while the middle finger of the upper hand pushes upwards on the occiput, encouraging flexion of the head, to avoid damage to the fetal cervical spine.